One of the cost of production problems that holds algae back as a major biomatter resource is an efficient cost-effective method of harvesting and removing the water from the algae for it to be processed.

Algae have the potential to be a very efficient biofuel producer.  The one cell plant produces oil that can be processed to create a useful biofuel.  Biofuels made from plant material are considered important alternatives to fossil fuels.  The carbohydrate portion can be used food or to make more fuel.

The SU team’s new technique builds on previous research in which microbubbles were used to improve the way algae is cultivated.  The early work used the microbubble technology to improve algae production methods, allowing producers to grow crops more rapidly and more densely and earned Zimmerman and the team the Moulton Medal, from the Institute of Chemical Engineers.  The research paper is published in Biotechnology and Bioengineering.

Professor Zimmerman outlines the story saying, “We thought we had solved the major barrier to biofuel companies processing algae to use as fuel when we used microbubbles to grow the algae more densely. It turned out, however, that algae biofuels still couldn’t be produced economically, because of the difficulty in harvesting and dewatering the algae. We had to develop a solution to this problem and once again, microbubbles provided a solution.”

Microbubble Algae Separation at the University of Sheffield. Click image for the largest view.

Microbubbles have been used for flotation before: water purification companies use the process to float out impurities, but it hasn’t been done in this context, partly because the previous methods have been very expensive.

The new system developed by Zimmerman´s team uses as little as one tenth of a percent of the energy to produce the microbubbles.  Additionally, the cost of installing the Sheffield microbubble system is predicted to be much less than existing flotation systems.

Zimmerman explains the technology saying, “What we’ve found is that we can separate the microalgae from the water or harvest it using microbubbles that are created by a fluidic oscillator. A fluidic oscillator switches flows rapidly from one outlet to another, using feedback to do so with no moving parts. It is like an opening and closing mechanical valve that results in pulsing flow. Our bubbles are made under laminar flow and we use practically no more energy than is required to make the interface of the bubble.”

As a result of the low energy input, the bubbles rise very slowly, which is crucial as it means the algae particles can attach themselves to the bubbles more easily. Two chemicals added to the liquid in the process, a flocculant and a coagulant to help the algae bond to the rising microbubbles.

“The idea is to create a surface on the algae particles that is hydrophobic so the microbubbles are attracted to it,” said Zimmerman. When the bubbles and the particles reach the surface, the flocculant and the coaggulant keep the algae in a fixed layer. The blanket of algae can then be skimmed off the surface with something such as a belt skimmer. “In the lab, we use a knife.”

Zimmerman explained that the process is much cheaper than attempting to make microbubbles through an industrial process known as dissolved air flotation, which generates bubbles that are too turbulent to harvest algae.

Next up for the technology is to develop a pilot plant to test the system at an industrial scale.  Professor Zimmerman is already working with Tata Steel at their site in Scunthorpe, where Tata Steel is recovering and using CO2 from their flue-gas stacks.  Zimmerman and Tata plan to continue the partnership to test the new system.

The SU team’s technology may have other soon to be used attributes.  Lakes that have a build-up of nutrients causing algal blooms to form called eutrophication, often attributed to agricultural fertilizers entering water bodies, need the algae harvested and removed instead of left to die and decompose.

The SU team is already in talks with Ken Shu, a scientific adviser to the Chinese government, to set up pilot-scale trials on remediating algal blooms in eutrophied lakes in China.

Zimmerman explains, “China has demographic drinking-water problems. They’re running out because the lakes that used to be used for drinking water are all eutrophied with algal blooms.”

It looks good in the lab.  A lot of ideas have came and went in trying to capture the algae cells in a low cost harvest.  Algae, naturally, are pretty good at keeping themselves separate with each basking in the sunlight. It’s a significant attribute that makes the very high productivity possible as well as makes the harvest problematic.

Lets hope the Brits have it nailed down now.

Hydrates are a water ice and usually a natural gas compound that have been explored by researchers as a source of alternative fuel or storage medium for CO2.  The PNNL researchers note at first discovery the hydrogen storage value approaches the goal of a Department of Energy standard and could make hydrogen hydrates practical and affordable for storage.

Using computer analysis of the ice and gas compound reveals key details of its structure and researchers have accurately quantified the molecular-scale interactions between the gases of either hydrogen or methane, also known as natural gas – and the water molecules that the form cages around them.

The research team’s results from the Department of Energy’s Pacific Northwest National Laboratory were published in Chemical Physics Letters online December 22, 2011.

While hydrogen is the most interesting use of hydrates, PNNL chemist Sotiris Xantheas the lead author said, the results could also provide insight into the process of replacing methane with carbon dioxide in the naturally abundant “water-based reservoirs.”

Here’s the marvel revealed in the research as put by Xantheas, “Current thinking is that you need large amounts of energy to push the methane out, which destroys the scaffold in the process. But the computer modeling shows that there is an alternative low energy pathway. All you need to do is break a single hydrogen bond between water molecules forming the cage – the methane comes out, and then the hydrate reseals itself.”  This revelation has major implications on natural gas recovery.

Previously Xantheas and the colleagues used computer algorithms and models to examine the water-based, ice-like scaffold that holds the gas. Water molecules form individual cages made with 20 or 24 molecules. Multiple cages join together in large lattices. But those scaffolds were empty in the earlier analysis.

To find out how fuels can be accommodated inside the water cages, Xantheas and colleague Soohaeng Yoo Willow built computer models of the cages with either hydrogen gas – in which two hydrogen atoms are bound together – or methane gas, a small molecule made with one carbon and four hydrogen atoms.

In the hydrogen hydrates, the idea that could potentially be used as materials for hydrogen fuel storage, a small hollow cage made from 20 water molecules could hold up to a maximum of five hydrogen molecules and a larger cage made from 24 water molecules could hold up to seven.

The maximum storage capacity equates to about 10 weight-percent, or the percentage of hydrogen by mass in the chunks of ice.

However packing hydrogen in that tight puts undue strain on the system.  But it nearly doubles the DOE’s goal for hydrogen storage above a 5.5 weight-percent.

Now the story gets intuitive, innovative and just clever.  Experimentally, hydrogen storage researchers typically measure much less storage capacities. The computer model showed them why: The hydrogen molecules tended to leak out of the cages, reducing the amount of hydrogen that could be stored.

The PNNL team found that adding a methane molecule to the larger cages in the pure hydrogen hydrate prevented the hydrogen gas from leaking out. The computer model showed the researchers that they could store the hydrogen at high pressure and practical temperatures, and release it by reducing the pressure, which melts it.

Understanding how the gas interacts and moves through the cages can help chemists or engineers store gas and remove it at will.

Willow and Xantheas’ computer simulations showed that hydrogen molecules could migrate through the cages by passing between the figurative bars of the water cages. However there’s a problem to work out, the cages also had gates: Sometimes a low-energy bond between two water molecules broke, causing a water molecule to swing open and let the hydrogen molecule drift out. The “gate” closed right after the molecule passed through to reform the lattice.

With methane hydrates, some fuel producers want to remove the gas safely to use it.  So, Willow and Xantheas tested how methane could migrate through the cages.

The water cages are only big enough to comfortably hold one methane molecule, so the chemists stuffed two methane molecules inside and watched what happened. Quickly, one of the water molecules forming the cage swung open like a gate, allowing one methane molecule to escape. The gate then slammed shut as the remaining molecule scooted into the middle of the cage.

Xantheas explains, “This process is important because it can happen with natural gas. It shows how methane can move in the natural world. We hope this analysis will help with the technical issues that need to be addressed with gas hydrate research and development.”

The team’s work is still all in the computer, but the insight should allow a broad spectrum of researchers a blueprint for experimentation and the beginning steps of processes and engineering.  The best news is the storage rate is very high and the temperatures are in an easy to access zone with common refrigeration and low energy requirements to do the warm up.  The engineering challenge to today is substantial, but some very good minds are going to light up with this news.

Earlier a team discovered that bisabolane, a member of the terpene class of chemical compounds holds high promise as a biosynthetic alternative to No.2 diesel fuel that generated keen interest in the green energy community and the trucking industry. This team identified bisabolane as a potential new advanced biofuel that could replace No.2 diesel, today’s standard fuel for diesel engines, with a renewable alternative that’s produced in the United States.

Using the tools of synthetic biology, the researchers engineered strains of bacteria and yeast to produce bisabolene from simple sugars, which was then hydrogenated into bisabolane. While showing much promise, the yields of bisabolene have to be improved for microbial-based production of bisabolane fuel to be commercially viable.

Now a second team led by bioengineers Paul Adams and Jay Keasling, solved the protein crystal structure of an enzyme in the Grand fir (Abies grandis) called “Abies grandis α-bisabolene synthase” (AgBIS) that synthesizes bisabolene, the immediate terpene precursor to bisabolane.  But when AgBIS is engineered into microbes, the enzyme results in a bottleneck that hampers the conversion by the microbes of simple sugars into bisabolene.  The opportunity suddenly became a problem.

AgBIZ Enzyme. Click image for more info.

Adams, a leading authority on x-ray crystallography, explains what the team has figured out saying, “Our high resolution structure of AgBIS should make it possible to design changes in the enzyme that will enable microbes to make bisabolene faster. It should also enable us to engineer out inhibition effects that slow throughput, and perhaps also engineer the enzyme to produce other kinds of fuels similar to bisabolane.”

The paper “Structure of a Three-Domain Sesquiterpene Synthase: A Prospective Target for Advanced Biofuels Production.” About AgBIS has been published at the Cell Press journal Structure.

Pamela Peralta-Yahya, a lead member of the earlier JBEI team as well as the current team discusses the situation saying, “The inefficient terpene synthase enzyme is one of the bottlenecks in the metabolic pathway used by the engineered microbes. Knowing the AgBIS crystal structure will guide us in engineering it for improved catalytic efficiency and stability, which should bring our bisabolene yields closer to economic competitiveness.”

Ryan McAndrew a co-lead author explains Peralta-Yahya and her colleagues determined that the AgBIS enzyme consists of three helical domains, the first three-domain structure ever found in a synthase of sesquiterpenes – terpene compounds that contain 15 carbon atoms. The discovery of this unique structure holds importance on several fronts.

McAndrew continues, “That we found the structure of AgBIS to be more similar to diterpene (20 carbon terpene compounds) synthases not only provides us with insight into the function of these less well characterized enzymes, it also provides us with clues to the evolutionary heritage as the archetypal three-domain terpenoid synthases became two-domain sesquiterpene synthases in plants. Furthering our knowledge of the structures and functions of terpenoid synthases may prove to have abundant practical applications aside from advanced biofuels because these enzymes produce a wide variety of specialized chemicals.”

The look into AgBIS was made possible by the protein crystallography capabilities of Berkeley Lab’s Advanced Light Source (ALS) for synchrotron radiation, and the first of the world’s third generation light sources.  The JBEI team used three of the five protein crystallography beamlines operated by the Berkeley Center for Structural Biology (BCSB).  Adams, who headed the BCSB from 2004 to 2011, tells us, “We needed to use multiple beamlines because we collected data on several crystals – the protein by itself, and the protein with different inhibitors/cofactors.”

That’s a lot of unfamiliar chemistry terms in one post.  To summarize, the JBEI teams have found AgBIS will convert sugars to the heavier chemicals in the 15-carbon atom range – which is where development needs to be for diesel and other products of that molecular size.  But when AgBIS was engineered in the activity came up short, and the question ‘why?”, now has a visual means of understanding and that offers a much clearer means to manipulate the structure and likely, redevelop a new enzyme that could be very productive indeed.

It’s still way, way early in the research.  Having a leading candidate for engineering bio organisms to join in making the products in the 15 carbon atom and up range is very enticing news.  The ability to make these fuels over just extracting them from plants offers massive growth potential.

Now a division of DuPont, Pioneer has entered into a deal with NexSteppe for collaboration in developing

Sweet Sorghum At An Oklahoma State U. Test Plot. Click image for the largest view.

sorghum varieties.  The expectation for expert observers is the collaboration is meant to bring a new high-yield crop to growers, or hybridize a crop that has worked spectacularly well elsewhere to work in localized conditions.

Sweet sorghum is a versatile crop.  It may be destined as a rotation crop, or used in place of cover crops to bring in a second economically valued harvest.  Sweet sorghum hybrids could be high biomass hybrids in order to create additional feedstock options for biofuels, biopower and biobased products.

The deal is Pioneer has made an equity investment in NexSteppe and will provide knowledge, resources and advanced technologies to help NexSteppe accelerate the breeding and commercialization of new hybrids of these crops in the United States and Brazil.  That’s a deal in Iowa.

In Illinois U.S. Department of Energy’s Advanced Research Projects Agency-Energy’s Plants Engineered to Replace Oil program has awarded a $5.7 million dollar contract to Chromatin, Inc.

The U.S. DOE contract is to fund a three-year program to develop new varieties of sweet sorghum for use as an energy-rich, low cost feedstock for transportation fuels. Chromatin is working to develop non-food varieties of sorghum that have higher energy content to produce low-cost and renewable transportation fuel, high value chemicals and a high-BTU source of bio-oil. Sweet sorghum can produce very high biomass yields with less water and fewer chemical inputs than major food crops and is grown on land that is not devoted to food production.

Hybrid sweet sorghum is expected to produce both sugar and higher yields of biomass.  Forecasts propose it can be planted on dry marginal pastureland, and because it has has a short growing season it should suitable for crop rotation with other crops, perhaps wheat an other dry land grains.

Native sorghum is naturally drought and heat-tolerant and has the ability to grow in marginal rainfall areas with high temperatures where it is difficult to grow other crops.  From central Texas up through Oklahoma where a drought is underway sweet sorghum may offer a better cash income than pasture and could double up the income from wheat.

You may have noticed that the Pioneer/NexSteppe deal is also looking to Brazil. Sweet sorghum can be used as a complement to sugarcane in existing Brazilian sugar to ethanol mills, and as a feedstock for advanced biofuels and other bio-based products produced from sugars.

DuPont has another motive as well, its Industrial Biosciences business, operates and develops industrial processes that use sugar as a feedstock.

Just last month NexSteppe announced it had raised $14 million in its second round of funding. The company said then that it would use the proceeds from the round to scale up its sweet sorghum, high biomass sorghum and switchgrass breeding programs, and to advance its first products toward commercialization.

The food vs. fuel debate gas died down for now.  The U.S. is exporting ethanol to eager customers as those markets learn that ethanol is a top-flight gasoline extender.  The tired arguments run by the liars that figure have pretty much collapsed by real world numbers whose figures show ethanol added to gasoline is becoming a world wide phenomena.

A worldwide ethanol additive at 10% could eventually shave 4 to 5 million barrels a day from crude oil demand.  It also a number than can grow.

Soon there will be little doubt that the infrastructure for fueling ethanol fuel cells is in place ready for the technology.

Meanwhile, sweet sorghum has better tolerance for more marginal land than corn, and a far wider growing region than sugar cane, which is only tropical.  The ethanol market is getting another crop that should take out the feedstock worry of unavailable, unaffordable unsustainable or unreliable.

E-10 to E-85 are about to become worldwide choices for transport fuel.

It isn’t possible for people to join in the world of trade, increasing incomes and raising living standards to the developed world’s condition without getting through the food gathering and preparation needed at far more productive time scales.  Increasing human population is making the food issue even more complex, and much of the forests of the less developed world are disappearing and the result is soil destruction.  Tree growth can’t compensate fast enough.

Bamboo. Click image for the largest view.

Bamboo just might.

Bamboo is a plant not often associated with Africa because it’s being not exploited.  But it grows there as well as in Asia, and it can be used as an alternative source of energy.  China, the International Network for Bamboo and Rattan (INBAR) and a partnership among African nations and communities are working to substitute bamboo charcoal and firewood for forest wood. The European Union and the Common Fund for Commodities are funding the initiative. The market is huge, 80 percent of the rural population in sub-Saharan Africa depend naturally occurring fuel sources for their energy needs.

Dr. J. CoosjeHoogendoorn, Director General of INBAR says, “Bamboo, the perfect biomass grass, grows naturally across Africa and presents a viable, cleaner and sustainable alternative to wood fuel. Without such an alternative, wood charcoal would remain the primary household energy source for decades to come with disastrous consequences.”

Initial successes with bamboo charcoal in Ghana and Ethiopia, which have put bamboo biomass at the center of renewable energy policies, are spurring interest in countries across the continent and prompting calls for greater investment in bamboo-based charcoal production as a ‘green biofuel’ that could fight deforestation and soil degradation.

INBAR’s bamboo as sustainable biomass energy initiative is the first to transfer bamboo charcoal technologies from China to sub-Saharan Africa to produce sustainable ‘green biofuels’ using locally available bamboo resources.

Roughly it takes seven to 10 tons of raw wood to produce one ton of wood charcoal, making wood fuel collection an important driver of deforestation on a continent of nearly one billion people, who have few alternative fuel sources.

Professor Karanja M. Njoroge, Executive Director, Green Belt Movement points out, “Bamboo grows naturally across Africa’s diverse landscapes, but unlike trees, it regrows after harvest and lends itself very well for energy plantations on degraded lands. We should put it to good use to provide clean energy for the continent.”  Sub-Saharan Africa has over 2.75 million hectares of bamboo forest, equivalent to roughly 4 per cent of the continent’s total forest cover.

MelakuTadesse, National Coordinator for Climate Change Unit at Ethiopia’s Ministry of Agriculture explains the route to sustaining a bamboo fuel system, “With further investment and policy reform, community kiln technologies could be up-scaled to reach thousands of communities in Ethiopia.”

The resource is there; bamboo is one of the fastest-growing plants on the planet and produces large amounts of biomass, making it an ideal energy source. Tropical bamboos can be harvested after three years, compared to the two to six decades needed to generate a timber forest.
The entire bamboo plant, including the stem, branch and its rhizome, can be used to produce charcoal, making it highly resource-efficient, with limited waste. Its high heating value also makes it an efficient fuel.

The charcoal production is like any other, the controlled burning of bamboo in kilns, whether traditional, metal, or brick.

The partnership is looking at technology adapted to produce larger quantities of charcoal to serve a larger number of rural and urban communities as well as to produce bamboo charcoal briquettes that are ideal for cooking because it burns longer, produces less smoke and air pollution than ‘natural’ charcoal.

China, a global leader in the production and use of bamboo charcoal, where the business sector is worth an estimated  $1 billion a year and employs over 60,000 people in more than 1,000 businesses is bringing industrial partners, including the Nanjing Forestry University and Wenzhao Bamboo Charcoal Company who are helping to adapt equipment like brick kilns, grinders and briquette machines, and hand tools, for bamboo charcoal and briquette production using the local materials.

The idea brings energy production, jobs and sales to customers.  In addition to charcoal, bamboo offers many new opportunities for income generation.  It is being processed into a vast range of wood products, from floorboards to furniture and from charcoal to edible shoots.

In Ghana where the first stage of the idea is underway, 300 micro small enterprises in the program area have been established with over 2,000 growers cultivating bamboo as well as charcoal production and some 7,000 low-income local households are expected to use bamboo charcoal as cooking fuel by the close of the project year in 2014.  A total of 505 metric tons of bamboo charcoal have been produced for October and November of 2011.

That has led and supports efforts of cultivating bamboo, having seen the planting of 11,733 seedlings out of 14,880 seedlings propagated from 15 different species selected across the globe.

Ghana is motivated – bamboo technology is a welcome concept because the rate of forest depletion shows the country has lost about 6.6 million hectares of forest cover since the beginning of the last century and has the highest rate of deforestation of 2.19% globally – a disaster in the making.

Bamboo could be an African turning point, the partnership envisions leaders, policy-makers, private sector, metropolitan, municipal and district assemblies, religious and traditional authorities as well as civil society organizations leading the crusade towards saving the forests and the environment from destruction and end its ability to support the human population.

It’s all really hopeful in a continent where human life remains so challenged, politically adrift and at the mercy of nature’s competitive onslaughts on life. It time for Africans to help themselves much more and a technology transfer from China may just do the trick.

We wish them luck and success and a Thank You to the Chinese.

Aalto's Sample of Wood Chips for Butanol Production. Click image for the largest view.

Butanol is particularly suitable as a transport fuel because it is not water-soluble and has higher energy content than ethanol.  Moreover there is pressure building in the European Union as new fuel requirements state fuel must contain 10 percent biofuel by 2020.

A clear benefit of butanol is that a significantly large percentage – more than 20 percent of butanol, can be added to fuel without having to make any changes to existing combustion engines. The nitrogen and carbon emissions from a fuel mix including more than 20 per cent butanol are significantly lower than with fossil fuels. For one point of comparison, the incomplete combustion of ethanol in an engine produces volatile compounds that increase odor nuisances in the environment. Estimates indicate that combining a butanol and pulp plant into a modern biorefinery would provide significant synergy benefits in terms of energy use and biofuel production.

The significant new breakthrough in the study is to successfully combine modern wood pulp handling – and new biotechnology. Finland’s advanced forest industry provides particularly good opportunities to develop this type of bioprocesses.

Wood biomass is made up of three primary substances, the cellulose, hemicelluloses and lignin. Of these three, cellulose and hemicellulose can be used as a source of nutrition for microbes in a bioprocess. Along with cellulose, the Kraft process that is currently used in pulping produces black liquor, which can already be used as a source of energy. But black liquor is not suitable for feeding microbes. In the Aalto study, the pulping process was altered so that, in addition to cellulose, the other sugars remain unharmed and can therefore be used as raw material for microbes.

The most commonly used raw materials in bio based butanol production so far have been starch and cane sugar. In contrast to this, the starting point in the Aalto University study was to use only the lignocellulose, otherwise known as wood biomass, which does not compete with food production.  The publication of the results are in Bioresouce Technology.

When wood biomass is boiled in a mixture of water, alcohol and sulfur dioxide, all parts of the wood – cellulose, hemicellulose and lignin – are separated into clean fractions. The cellulose can be used to make paper, nanocellulose or other products, while the hemicellulose is efficient microbe raw material for chemical production. The Finns’ new advantage of this new process is that no parts of the wood sugar are lost or wasted.

The published estimates indicate that combining a butanol process and a pulp plant into a modern biorefinery would provide significant synergy benefits in terms of energy use and biofuel production.  The program at Aalto University is developing new skills based on national strengths and related to the refining of biomass. The overall aim of the project is to increase the refining value of forest residues that cannot be utilized in, for example, the pulp process.

The lab results for the process successfully used batch and continuous production of acetone, butanol and ethanol (ABE).  Initially, batch experiments were performed using spent liquor to check the suitability for production of ABE. Maximum concentration of total ABE was found to be 8.79 g/l using 4-fold diluted liquor supplemented with 35 g/l of glucose.  In completing the course of testing the team returned to batch processing for the highest yields.

The Finn effort looks to have good results that may be applied wherever forests are harvested, especially where paper is made.  Butanol is the alcohol most desirable for a drop in gasoline replacement – producers won’t need to look far for customers/

The next step is to come out of the lab for a little real outside world testing.  There’s a large stock of black liquor from papermaking that could use a high value process to extract the value in a better way.  It looks like the Finn team might have it.

The team of JBEI researchers, working with researchers at the U.S. Department of Agriculture’s Agricultural Research Service (ARS), has demonstrated that introducing a maize (corn) gene into switchgrass, a highly touted potential feedstock for advanced biofuels, more than doubles (250 percent) the amount of starch in the plant’s cell walls and makes it much easier to extract polysaccharides and convert them into fermentable sugars.

Switchgrass With Corn Gene. Click image for more info.

The gene, a variant of the maize gene known as Corngrass1 (Cg1), holds the switchgrass in the juvenile phase of development, preventing it from advancing to the adult phase.

Blake Simmons, a chemical engineer who heads JBEI’s Deconstruction Division and one of the principal investigators for the research said, “We show that Cg1 switchgrass biomass is easier for enzymes to break down and also releases more glucose during saccharification. Cg1 switchgrass contains decreased amounts of lignin and increased levels of glucose and other sugars compared with wild switchgrass, which enhances the plant’s potential as a feedstock for advanced biofuels.”

The research paper results have been published in the Proceedings of the National Academy of Sciences, entitled “Overexpression of the Maize Corngrass1 MicroRNA Prevents Flowering, Improves digestibility, and Increases Starch Content of Switchgrass.”

Lignocellulosic biomass is the most abundant organic materials on earth. Studies have consistently shown that biofuels derived from lignocellulosic biomass could be produced in the United States in a sustainable fashion and could replace today’s gasoline, diesel and jet fuels on a gallon-for-gallon basis.  Nature, however, does not make it easy. Unlike the starch sugars in grains, the complex polysaccharides in the cellulose of plant cell walls are locked within a tough woody material called lignin.

Among potential crop feedstocks for advanced biofuels, switchgrass offers a number of advantages. As a perennial grass that is both salt- and drought-tolerant, switchgrass can flourish on marginal cropland, does not compete with food crops, and requires little fertilization. A key to its use in biofuels is making it more digestible to the fermentation microbes.

The magic is in the choice of the gene offering the expression.  George Chuck, lead author of the paper and a plant molecular geneticist who holds joint appointments at the Plant Gene Expression Center with ARS and the University of California (UC) Berkeley explains, “The original Cg1 was isolated in maize about 80 years ago. We cloned the gene in 2007 and engineered it into other plants, including switchgrass, so that these plants would replicate what was found in maize. The natural function of Cg1 is to hold plants in the juvenile phase of development for a short time to induce more branching. Our Cg1 variant is special because it is always turned on, which means the plants always think they are juveniles.”

Chuck and his colleague Sarah Hake, another co-author of the paper and director of the Plant Gene Expression Center, proposed that since juvenile biomass is less lignified, it should be easier to break down into fermentable sugars. Also, since juvenile plants don’t make seed, more starch should be available for making biofuels. To test this hypothesis, they collaborated with Simmons and his colleagues at JBEI to determine the impact of introducing the Cg1 gene into switchgrass.

The result astonishes – in addition to reducing the lignin and boosting the amount of starch in the switchgrass, the introduction and overexpression of the maize Cg1 gene also prevented the switchgrass from flowering even after more than two years of growth, an unexpected but advantageous result.  “The lack of flowering limits the risk of the genetically modified switchgrass from spreading genes into the wild population,” said Chuck.

Its not a perfect answer yet.  For example, the Cg1 switchgrass biomass still required a pre-treatment to efficiently liberate fermentable sugars.  But then all the other cellulose based systems do as well.  Then the questions about propagation and cultivation need addressed.

Simmons looks at the results and the future about where it should lead saying, “The alteration of the switchgrass does allow us to use less energy in our pre-treatments to achieve high sugar yields as compared to the energy required to convert the wild type plants. The results of this research set the stage for an expanded suite of pretreatment and saccharification approaches at JBEI and elsewhere that will be used to generate hydrolysates for characterization and fuel production.”

Another point, which may prove more worthwhile over time, pertains to the mechanism by which Cg1 is able to keep switchgrass and other plants in the juvenile phase. “We know that Cg1 is controlling an entire family of transcription factor genes,” Chuck said, “but we have no idea how these genes function in the context of plant aging. It will probably take a few years to figure this out.”

The team’s results, about a week earlier than a study out of the UK, illustrate how far and fast biomass production could go.  The UK folks seem to think that about a fifth of global energy demand could be met by biomass without harming food production.  The article about the study notes there has been a debate raging.  One wonders why there is any debate at all . . .

250% is quite a disrupter and challenges the cellulosic industry to get the processing costs down.

Now the question comes if the gene will transfer into miscanthus as well.  If it does and one or both field trial as well as the lab trials the biomass outlook will be vastly changed for the better.

For now feeding and fueling humanity uses synthesized ammonia in NH3 form by a process that requires high temperatures and pressures that consumes an estimated 1.5 percent of the world’s energy use.

The SLAC team has identified a key atom that researchers have sought for more than a decade.  The atom lies at the heart of the crucial enzyme called nitrogenase.    Nitrogenase is the primary natural key in converting nitrogen in the air into a form that living things can use.

Scientists have long sought to determine the structure of this enzyme; because the hope to eventually reverse-engineer it and mimic nature’s gentle version of the reaction.

Chemist Serena DeBeer of Cornell University and the Max Planck Institute for Bioinorganic Chemistry, who led the team that performed crucial experiments at SLAC said in the press release, “The fascination with this enzyme is the fact that it enables this reaction to take place at room temperature and atmospheric pressure.”

Nitrogenanse Research Team Members. Click image for more info.

The race has been close to identifying the mystery atom.  It ended in a photo finish, in the Nov. 18 issue of Science, two independent teams; using different approaches, identified the atom as carbon.

The carbon atom has eluded scientists because of its sequestered location inside a cluster of metal atoms. The key in the SLAC’s team’s research was a technique called X-ray emission spectroscopy, or XES, which co-author Uwe Bergmann of SLAC had developed over the past decade.

FeMoco and P-Nitrogenase Model Per the Study. Click image for more info.

The SlAC team needed a trick to find the one important carbon inside the metal cluster. They used an intense beam of X-rays from the Stanford Synchrotron Radiation Lightsource to knock the innermost electrons out of iron atoms in the cluster. Normally other electrons from iron would fill this hole; but there was a tiny chance, much less than one in a thousand, that the hole would be filled by an electron belonging to a neighboring atom, and thus emit X-rays characteristic of the neighbor’s identity. It was this subtle feature in the X-ray emission spectrum that revealed that a carbon atom, rather than a nitrogen or oxygen, was bound to the iron atoms in the cluster.

Bergmann said, “This was a simple but important question and we were able to give a straightforward answer. I think this will have a big impact not only on the understanding of nitrogenase but on the use of X-ray emission spectroscopy.”

It is critically important to understand this as the preparation of food and fuel supplies in quantities for people numbering in the billions with high living standards in mind is a huge production, logistical and economic challenge.

The cluster of metal atoms is where nitrogen molecules from the air, the N2, are broken down and recombined to ammonia and other compounds by microbes in the soil. Then plants can take it up and spread it through the food chain.

It’s how we get roughly half of the nitrogen into the food supply for our bodies; the rest comes from artificial fertilizers primarily made via the Haber-Bosch reaction, the resource-intensive method widely used to convert atmospheric nitrogen to NU3 ammonia using air and natural gas for the hydrogen supply and heat for the process.

Researchers knew a decade ago that the central atom in the metal cluster must be nitrogen, oxygen or carbon. Each would affect the reaction differently. But how to identify this atom among the 20,545 total carbon atoms, 11,026 oxygen atoms and 5,431 nitrogen atoms in a very complex enzyme?

The perspective offered by the press release comes from a third party – chemist Brian Hoffman of Northwestern University, who has investigated nitrogenase for 30 years but was not involved in these studies saying, “Because it’s sequestered in the middle of a bunch of metal atoms and you’ve got no way to get your hands on it, it’s a really hard problem. What the team has done would appear to be a classic case where new technology leads to new science.”

So it is.  Note again quantities of the list of atoms of the three main elements in the nitrogenase enzyme. And that’s not including those metals mentioned.

It’s going to take a lot of science to synthesize that enzyme.  But when it’s done, the size of the market and the potential to the world’s economy will open a new door to one of the largest markets in history.

Shortening up the process from biomass to hydrocarbons has long been an idea of intense interest, and usually skipped over to the easier fermentation, pyrolysis and other schemes to get molecular change.

Maine is driven by circumstances, a lot of wood, some 6 million green tons of additional available biomass, according to a 2008 Maine Forest Service Assessment of Sustainable Biomass Availability.  The new process suggest the biomass could yield 120 million gallons per year of gasoline, diesel, heating oil and kerosene mixtures while providing all the steam and power needs of the processing plants.

The whole of the U.S. transportation industry, which is dependent on hydrocarbon fuels because of their high energy density, could benefit from the revolutionary finding.

The new process was developed by M. Clayton Wheeler, a UMaine associate professor of chemical and biological engineering, and undergraduate students in his lab.  Based on a mixed-carboxylate platform, the fuel has been determined to have a number of properties that make it better suited to serve as a drop-in fuel than many alternative fuels being widely researched and, bravely suggested, even those currently on the market.

In an early round of analysis, the UMaine oil product was found to have boiling points that encompass those of jet fuel, diesel, and gasoline. Further refinement to meet emissions standards would be needed in order to use the UMaine oil in vehicles that drive on public ways, but Wheeler believes the oil can be refined as simply as any other current oil at a standard refinery.

The process creating the oil is known as thermal deoxygenation (TDO) is relatively simple, Wheeler says, and will work on the cellulose found in wood or other substances that contain cellulose or carbohydrates and the process requires no catalysts or hydrogen, and is “a spin on chemistry used to make acetone back in the 1800s.”

Wheeler says, “The process is unique. No one else in the world is doing this.”

The TDO process starts with the conversion of cellulose to organic acids. The acids are combined with calcium hydroxide to form a calcium salt. That salt is heated to 450 degrees Celsius (900 degrees Fahrenheit) in a reactor, which constantly stirs the salt. This produces a reaction resulting in a dark amber-colored oil.

Here it gets very interesting -the reaction removes nearly all of the oxygen from the oil, which is a key step that distinguishes TDO from other biofuel processes. Oxygen is removed from as both carbon dioxide and water, and without the need for any outside source of hydrogen to remove the oxygen. Therefore, most of the energy in the original cellulose source is contained in the new oil.

The research paper, free with a registration, is titled “Energy Densification of Levulinic Acid by Thermal Deoxygenation,” at Green Chemistry.

Wheeler explains, “Biomass has a lot of oxygen in it. All of that oxygen is dead weight and doesn’t provide any energy when you go to use that as a fuel. If you’re going to make a hydrocarbon fuel, one of the things you have to do is remove oxygen from biomass. You can do it by using hydrogen, which is expensive and also decreases the energy efficiency of your process. So if there’s a way to remove the oxygen from the biomass chemically, then you’ve densified it significantly.  Our oil has less than 1 percent oxygenates. No one else has done anything like this. ”

Wheeler’s lab team recently used unpurified, mixed carboxylates, which were produced from grocery store waste such as banana peels, cardboard boxes and shelving to successfully make a batch of the fuel. The use of municipal solid waste illustrates another important point about the potential of the UMaine fuel – it does not require an uncontaminated cellulose source, which makes the TDO process and resulting oil even more attractive. Many other pathways to hydrocarbons require purified feedstocks or intermediates, which adds more complexity and cost to their processes.

“You don’t need pure wood or pure cellulose,” says Wheeler. “Anytime you can use something without having to separate it, your costs go down.”

Wheeler and his team already have the ability to produce several liters of the fuel per month in the laboratory. The process can be scaled up using equipment and chemicals commonly found in facilities such as some pulp mills.

This has to snap around the minds of very large alternative fuel users.  If it will scale up a major city’s municipal waste could offer a medium size oil company a very large continuous supply of raw oil for refining.  It should also put an attractive value in the garbage and trash.  Imagine people not pitching out the trash or picking it up for some extra money.

It may also scale to local area farm cooperatives that could pop up worldwide.  The potential here is incredible.

This is a major congratulatory event for UMaine, Wheeler and the team.

So taking the hint, researchers at the Oak Ridge National Laboratory’s BioEnergy Science Center (BESC) have undertaken to lead a first-of-its-kind study of the naturally occurring phenomenon in trees to spur the development of more efficient bioenergy crops.

The individual elements of tension wood have been studied previously, but now the BESC team is the first to use a comprehensive suite of techniques to systematically characterize tension wood and link the wood’s properties to sugar release.  The idea is produce more sugars for producing alcohols productively.

Oak Ridge National Laboratory’s Udaya Kalluri, a co-author on the study explained saying, “There has been no integrated study of tension stress response that relates the molecular and biochemical properties of the wood to the amount of sugar that is released.”

The BESC team is learning tension wood properties include an increased number of woody cells, thicker cell walls, more crystalline forms of cellulose and lower lignin levels, all of which are desired in an biofuel crop.  The work and the preliminary results have been published in Energy & Environmental Science.

Poplar Left Tension Wood Bottom Right Normal Wood Top Right. Click image for more info.

Kalluri continues, “Tension wood in poplar trees has a special type of cell wall that is of interest because it is composed of more than 90 percent cellulose, whereas wood is normally composed of 40 to 55 percent cellulose. If you increase the cellulose in your feedstock material, then you can potentially extract more sugars as the quality of the wood has changed. Our study confirms this phenomenon.”

Another benefit is the study’s cohesive approach also provides a new perspective on the natural plant barriers that prevent the release of sugars necessary for biofuel production, a trait scientists term as recalcitrance.

Co-author Arthur Ragauskas of Georgia Institute of Technology explains, “Recalcitrance of plants is ultimately a reflection of a series of integrated plant cell walls, components, structures and how they are put together. This paper illustrates that you need to use an holistic, integrated approach to study the totality of recalcitrance.”

The current study is an early step.  Using the current study as a model, the research team is extending their investigation of tension wood down to the molecular level and hope to eventually unearth the genetic basis behind its desirable physical features. Although today tension wood itself is not considered to be a viable feedstock option, insight gleaned from studying its unique physical and molecular characteristics could be used to design and select more suitably tailored bioenergy crops.

BESC director Paul Gilna said, “This study exemplifies how the integrated model of BESC can bring together such unique research expertise. The experimental design in itself is reflective of the multidisciplinary nature of a DOE Bioenergy Research Center.”

The research team spans three institutions including Georgia Institute of Technology with Marcus Foston, Chris Hubbell, Reichel Sameul, Seokwon Jung and Hu Fan; the National Renewable Energy Laboratory with Robert Sykes, Shi-You Ding, Yining Zeng, Erica Gjersing and Mark Davis, and ORNL’s own Sara Jawdy and Gerald Tuskan.

The study abstract shows the main point behind this step in the research was the recalcitrance issue that was upstaged by the increase in the sugar content.  One can credit the designers of the research with encompassing enough ground to find the new gem in the wide area comprehensive study design.

Improving the productivity of wood for fuel use is an excellent goal in itself, but the tension wood properties could have major implications across several industries where wood strength has importance.  Construction materials come to mind, stronger woods could affect the amount of wood needed – an attribute that’s shared with the fuel use of wood.  Better understanding wood can only make many things better, lower cost and more efficient. This is research effort well spent.